Allow DECIMAL Precision in WP_Query Meta Queries

[dominicp]

As of now, if we specify a precision for the DECIMAL type in WP_Query meta queries [e.g. DECIMAL(4,2)], the type is changed to CHAR. This transformation seems to happen here:

http://core.trac.wordpress.org/browser/tags/3.3.1/wp-includes/meta.php#L716

As a work around, we can add a filter to the get_meta_sql hook and manually change DECIMAL to DECIMAL(X,X) with a str_replace, but that seems pretty clumsy and it forces us to pick one level of precision for all meta queries.

As a solution, right above the line I have linked above, we could add a conditional that checks if the type starts with DECIMAL, and then uses a regex to check if the format for the precision is correct. Of course, another option would be to add a precision key to the meta query array like so:

array(
  'key' => 'meta_key',
  'value' => $value,
  'type' => 'DECIMAL',					
  'compare' => '>',
  'precision' => array( 4, 2 )
),

I apologize if this question has already been asked, or if I'm missing something obvious. But, to me it seems like the current system is a bit limiting. Thanks.